U.S. Pat. No. 7,749,532 discloses the use of doxycycline at sub-antimicrobial doses to treat rosacea. It further discloses a doxycycline composition consisting of (i) an immediate-release portion consisting of about 30 mg doxycycline, and (ii) a delayed-release portion consisting of about 10 mg doxycycline, in which the delayed-release portion is in the form of pellets coated with at least one enteric polymer. It further discloses that the enteric coating is such that there is no substantial release of doxycycline in the acidic stomach environment, and doxycycline is released only in the small intestine.
There remains a need in the art for a pharmaceutical composition of doxycycline which releases the drug in a continuous manner independent of the pH of the gastrointestinal tract. This is achieved by the pharmaceutical composition of the present invention which comprises specific amounts of doxycycline as immediate-release and controlled-release portions, in order to demonstrate a continuous release profile.